How does a radiator cool the engine?

Considering that car engines work on the principle of combustion, that is, the explosion of the air-fuel mixture inside the cylinders, it is not surprising that they generate a lot of heat. This, combined with the friction created by the many moving parts within an engine, means that engine temperature control is vital. Engines that operate at lower temperatures are more fuel efficient, produce more power and last longer. The job of a radiator is to keep the engine at the ideal temperature and prevent overheating.

The vast majority of cars use a closed-loop liquid cooling system to control engine temperature (some older cars are air-cooled). Liquid-cooled engines use a few common parts:

• Radiator
• Water pump
• Coolant
• Thermostat
• Coolant jacket
• Core heater

Engines have a system of channels running through the block and cylinder head, known as the coolant jacket. Through these channels flows a specially formulated liquid coolant (also known as antifreeze) mixed with water, absorbing engine heat. The water pump supplies coolant at a rate controlled by a thermostat. Eventually, the hot coolant flows from multiple channels of the cooling jacket to a single outlet before it reaches the radiator.

The main function of a heatsink is to provide a large surface area for the hot coolant so that the heat can be dissipated efficiently. Once it enters the radiator at one end, the single outlet splits into several smaller tubes known as core tubes. The core tubes run through many thin sheets of bent metal called cooling fins, which further increase the surface area. Radiators are usually mounted at the front of the engine behind the grille, above the air intake, or in some other location where there is strong airflow. Thus, when cold outside air passes through the cooling fins, the heat is dissipated as the vehicle moves forward. The fan provides cool air to the radiator when the vehicle is stationary or moving slowly in traffic.

The pressure generated by the water pump keeps the coolant flowing through the radiator. Once the heat has dissipated, the main pipes rejoin at the other end of the radiator, again pumping cold coolant through the coolant jacket. This is a continuous heating and cooling cycle that occurs as long as the engine is running.

A properly functioning radiator and cooling system is vital to the operation of your engine, so if a problem occurs, don't delay repairs. A coolant leak, a clogged radiator, a faulty thermostat, or a faulty water pump can cause an engine to overheat quickly. If your vehicle is overheating or overheating, call an AvtoTachki Certified Field Technician to inspect the problem immediately.